Lesson Notes By Weeks and Term - Primary 3

WEEK 5

Subject: Mathematics

Class: Primary 3

Term: 3^rd Term

TOPIC: Capacity

SUBTOPIC:  Capacity addition and subtraction of liters

BEHAVIOURAL OBJECTIVES: At the end of the lesson, pupils should be able to:

1. Recapitulate the standard measurements of some liquid
2. Convert liters to centiliters
3. Add liters correctly
4. Subtract liters correctly

CONTENT

CAPACITY ADDITION AND SUBTRACTION IN LITERS

Capacity is the measure of the amount of liquid in a container. The standard unit of

measuring capacity is the litre (l)

Small amount of liquid is measured in millilitre (ml) while large amount is measured in litres.

Table of capacity measure

10 milliliters ( ml) = 1 centiliter ( cl) 10 centilitres = 1 decilitre (dl)

10 deciliters = 1 litre (l) 10 litre = 1 decilitre (dl)

10 decilitres = hectolitre (hl)  10 hectolitres = 1 kilolitre (kl)

Note that

1 000ml  = 1 litre ( l ) 100 cl = 1 litre 1 000 l = 1 kilolitre (kl)

When converting a smaller capacity measure to a higher one, note the following:

1. a) From ml to cl, divide by 10 b) From cl to l, divide by 100
2. c) From ml to l, divide by 1 000 d) From l to kl, divide by 1 000

Examples

1. Convert 4 000ml to l =4000/1000l=4l
2. Convert 600cl to l = 600/100=6l

100cl = 6l

Exercise 1

Express the following in litres L

1. 2 000ML 2. 1 200CL 3. 650cl 4. 800cl 5. 5 000ml
2. 20 000ml 7. 900ml 8. 14 000ml 9. 700ml 10. 10 500ml

When converting higher capacity measure to a smaller capacity, note the following:

1. a) From cl to ml, multiply by 10 b) From l to cl, multiply by 100
2. c) From l to ml,, multiply by 1 000 d) From kl to l, multiply by 1 000

Examples

1. Convert 6 litres to cl

1 l􀆐 = 100 cl􀆐

6l = 100 × 6 = 600 clô€†

2. Convert 5.5 l to ml

1l  = 1 000 ml

5.5l = 5.5 × 1 000 ml = 5 500ml

Exercise 2

Convert the following to ml

1. 7 cl 2. 6.5 l 3. 10l 4. 8.5 l 5. 12l

Convert the following to ml

1. 2l 2. 10 cl 3. 1.5 l 4. 3 cl 5. 4l

Convert the following to l

1. 1.5 kl 2. 3kl 3. 4.3 kl 4. 0.8kl 5. 0.26kl
2. 1.2 kl 7. 0.3 kl 8. 0.15 kl 9. 1.04 kl 10. 3.13kl

Addition and subtraction involving litres

Examples

1. 2.38 l + 1.65 l

         = 2 · 38 + 1 · 65 = 4 · 03 l

2. 46.35l – 29.l6 l

            = 46 · 35 – 29 · 16 = 17 · 19 l

Exercise

Copy and complete the following.

1. 4 · 3 + 2 · 4l

2. 7 · 9 + 8 · 6l

3. 14 · 3+ 9 · 8l

4. 8 · 42+ 3 · 25l

5. 5. 12 · 86+ 4 · 91

6. 15 · 63+ 14 · 78

7. 3 · 175+ 18 · 134

8. 13 · 217+ 19 · 893

9. 27 · 398+ 24 · 923

10. 34 · 654+ 27 · 678

11. 49 · 415+ 50 · 687

12. 5 · 6− 2 · 4l

13. 9 · 2− 5 · 4l

14. 11 · 8− 6 · 9

15. 7 · 43− 2 · 19l

16. 20 · 24− 8 · 77l

17. 32 · 03− 18 · 15l

18. 32 · 714− 16 · 250l

19. 46 · 038− 15 · 71l

20. 53 · 412− 26 · 891l

21. 60 · 105− 42 · 314l

22. 76 · 964+ 9 · 087

23. 795 · 22+ 900 · 11l

24. 900 · 85+ 25 · 22

25. 18.23l + 19.47l 26. 26.08l + 34.971l 27. 41.376l+ 39.8l

28. 30.317l – 12.888l 29. 46.053l – 18.94l 30. 61.7l – 45.632l

TOPIC: Capacity

SUBTOPIC:  Capacity multiplication and division of liters

BEHAVIOURAL OBJECTIVES: At the end of the lesson, pupils should be able to:

1. Multiply in liter by whole
2. Divide in liter by whole
3. Appreciate liter as the unit of capacity

CONTENT

Multiplication and division involving litres

Multiplication

Example

Four cars each have 18.5 litres of petrol put in them. How much petrol is this?

18 · 5l

× 4

74 · 0

Exercise 1

Copy and complete the following.

1. 8·3l × 2

2. 7·1l × 8

3. 4·7l × 3

4. 5·9l × 4

5. 3.2l x 9

6. 9.4l x 7

7. 5.6l x 5

8. 6.2l x 6

9. 8.0l x 8

10. 1.7l x 9

11. 15.6l x 2 

12. 27.9l x 8

13. 36.3l x 7

14. 47.9l x 6

15. 54.8l x 9

16. 68.4l x 3

17. 43.6l x 7

18. 52.2l x 9

19. 39.9l x 6

20. 20.7l x 8

Division

Example

Three customers bought 5.7 litres of palm oil and then

shared it equally among themselves. How many litres did

each customer get?

5.7l ÷ 3 = 1.9 ô€† 5.7 /3 = 1.9 ô€†

1.9 􀆐

3 √5.7

Each customer got 1.9 litres.

Exercise 2

Work these out using the method in the example.

1. 4.8 l ÷ 4. 2. 8.4 l ÷ 6   3. 7.2l  ÷ 9.   4. 8.0  ÷ 5

5. 91.6/2􀆐 6. 74.7 /3. 7. 41.6/8􀆐 8. 53.6 /4

9. 3√ 17.1l 10. 7 √37.8l ô€† 11. 9 √66.6l ô€† 12. 5√ 89.5l ô€†

13. Divide 63.7 l􀆐􀀃by 7 14. Divide 83.2 􀆐 by 8

Examples

Word problems on capacity

1. 1. A drum contains 12.58 litres of water, another drum contains 15.71 litres of water.

How much water will the two drums hold?

One drum contains = 12 . 58l 

Another drum contains = 15 . 71l 

Both drums hold = 28 . 29l

2. A basin contains 30 litres of water. Bisi used 8.29 litres to wash. How much water is left in

the basin.

A basin contains 30 litres of water = 30 · 00 ô€†

                                                      + 8 · 29

                                                         21 · 71 ô€†

 used 8.29 litres

Amount of water left 30 – 8.29 litres

3. A car tank holds 40 litres of fuel. How many litres can three such cars hold?

One car 40 litres

Three cars 40 × 3 litres = 120 litres

4. 36 litres of milk was given to 4 pupils to share. How much milk will each pupil get?

No of litres to share = 36 litres 9 litres

4√ 36

     36

No of pupils to share it = 4

One pupil will get = 36 ÷ 4

Exercise 3

Word problems

1. 3.6l of water is poured into a bucket that already contains 2.9 litres of water. How much water is now in the bucket?

2. A tank is full and it contains 30 litres of petrol. 12.72 litres of this is used. How much petrol is left in the tank?

3. Five friends shared 4 litres of fanta equally. How many litres did each receive?
4. A station has only 92.4 litres of petrol left. This is shared equally by six customers. How many litres of petrol will each customer receive?

5. A trader sells 43 bottles of oil a day. Each bottle contains 0.6 litres of oil. How many litres did she sell?

6. Thirty-six children took 1.2 litres of water each with them on a journey. What was the total capacity of water taken?

7. A car uses 8.76 litres out of the 30.92 litres of petrol in the tank. What capacity of petrol is left in the tank?

8. A tanker emptied its water into two containers of 3 260 litres and 2 846 litres respectively. What is the capacity of the tank?

9. A bucket of water contain 7.2 litres of water when full. Equal amount is given to four goats. What capacity of water will each goat drink?

10. A driver bought 36.82 litres of petrol when traveling to Benin. On his way back he bought 48.45 litres. What is the total capacity of petrol bought?